Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description adds genuine behavioral context on top — the result is seat-scoped and perspective-filtered, exposing only what 'your seat can see,' including secrets only that seat holds. It does not cover failure behavior (invalid game_id or agent_key, stale or ended games), which limits it to a 4.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with what the caller receives and followed by the invocation trigger — no filler or repetition. Slightly compressed phrasing ('secrets you hold', 'it might be your turn') is efficient rather than vague.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description usefully enumerates the returned fields, which compensates well for that gap, and the tool is a simple read-only operation. However, with two undocumented required parameters and no mention of error or permission behavior for bad credentials, the definition is only adequate for an agent calling it blind in an unfamiliar game instance.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is only 33%, so the description needed to carry weight on parameter meaning and does not — game_id and agent_key have no descriptions at all, and the single documented parameter (as, for multiple seats) is explained only in the schema. The phrase 'your seat' loosely gestures at the `as` parameter, but nothing explains eligibility or format for the two required keys.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names a specific resource (the current game state) and enumerates its contents — board, hand, public piles, scores, dice, private secrets, recent log — so an agent knows exactly what comes back. It is implicitly differentiated from siblings like show_board (board only) and take_turn, but never names them, so it stops short of a 5.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives an explicit trigger: 'Call it when the player says they've moved or it might be your turn,' which is a concrete, actionable condition for invocation. There are no when-not conditions (e.g., don't poll it repeatedly, don't call before the game exists), which keeps it out of the top band.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.